Airplane pontoon



Aug. 1931- I w. H. WALLRAFF 1,817,047

AIRPLANE PONTOON Filed July 13, 1929 f/ .17 10 M Fz z I M Q m gwoentoz Waller If aZZra/ff bio mug Patented Aug. 4, 1931 WALTER H. WALLRAFF, OF ST. PAUL, MINNESOTA AIRPLANE PONTOON Applicationfiled July 13, 1929.

My invention relates to an improvement in airplane pontoons, wherein it is desired to provide a pontoon which will enable an airplane or hydroplane to rise from the surface of smooth water more quickly than has heretofore been possible.

The object of my invention is to provide an air duct or series of air ducts upon the lower surface of the pontoons of an airplane or hydroplane, and the sides of these air ducts having a series of small holes so positioned that compressed air or exhaust gasses, forced through the air ducts will direct jets of air or gas along the lower surface of the pontoon providing a film of air between the pontoon and the surface of the water, thus avoiding the action of the surface tension of smooth water upon the pontoon and facilitating the rising of the plane from the water.

It is a feature of my invention that any source of supply for the air or gas may be used. The air may be used from an air pressure tank placed either upon or within the pontoon or within the fuselage of the plane. The air source may be a small air pump in conjunction with the motor, which pump would be in operation only when needed. It would also be possible to bypass a portion of the exhaust gas through a connecting pipe to the air ducts upon the pontoons. Thus my invention could be used for virtually any type of plane using pontoons, and the air supply adapted for the style of plane for which it is used.

It is a feature of my invention that very little weight would be added to a plane so equipped with my air ducts. Thus by adding a very slight weight to the plane, the difficulty of rising from the surface of moderately smooth water will be to a large extent exterminated.

Additional objects and novel features of my invention will become apparent during the course of the following specification and claims.

In the drawings forming fication:

Figure 1 is a side elevation of a pontoon, showing the air ducts mounted in position.

part of this speci- Serial N0. 377,991.

Figure is a bottom showing a single Figure 3 1s a bottom view of the same,

air duct being used.

View of Figure 1,

showing an alternate form of construction using three parallel air duct-s.

Figure 1 illustrates a pontoon upon the surface of the water, showing the effect of surface tension pontoon.

Figure 5 upon the common type of illustrates my pontoon leaving the water surface, the air issuing through the air ducts destroying the effect of surface tension.

one illustrated. Extending face 10 of the from the rear of the lower surpontoon A along the lower surface longitudinally or in the direction of travel of the pontoon, I provide an air duct 11 or series of These air ducts are conne supply, upper derstood that the tank 12 parallelly extending air ducts 11.

cted to a source of such as the air tank 12 secured to the surface 13 of the pontoon A. It is unmay be within the pontoon or within the fuselage of the airplane.

In either side of the ducts 11 are formed a series of small holes 141.

A valve 15 prevents the air contained within the tank 12 from issuing through the holes 14 until needed. The valve 15 is operable by suitable means from within the fuselage of the air plane. In Figure 1 the lever 16 is attached to the handle 17 of the val ve l5 and extends through the floor of the fuselage, not illustrated in the drawings, so pulling the lever 16 the opened or closed.

The operation of my that by pushing or valve 15 may be pontoon is simple. As

the airplane or hydroplane increases its speed and prepares to leave the water, the

valve 15 is operated, all

through the air ducts sides of the ducts 11 and air between the pontoon 11. ducts is forced through the owing air to pass The air in the holes 14 in the projects in jets of A and the surface of the Water. The action of the compressed air breaks up the adhesion of the water to the pontoon and allows the plane to leave the Water With a minimum of effort. As soon as the pontoons are clear of the water, the air may be shut off until needed again.

The compressed air need not be atan extremely. high pressure in order that the correct action be accomplished, so that there Will be no great danger of an explosion in case of an accident to the plane from a high pressure of compressed air. If a tank of air is used, it may be pumped up before a flight, or it may be pumped up by means of a small air pump connected to the motor. Such a pump also could be used to force air directly into the air ducts as it is needed.

It would be possible to by-pass a portion of the exhaust gases through a connecting pipe to the air ducts, 11. In this way, the necessity of an air storage tank or an air pump driven by the motor would not benecessary, although it would then be essential to form the connecting pipe in such a manner that the heat of the exhaust would not endanger the plane.

I have described my invention as particularly adapted to pontoons, but I desire to have it understood that air ductsv may likewise be attached to the lower surface of boats or the boat-like bodies of fiyingboats, it being understood that a surface thus equipped will act in the manner of the pontoon described.

In providing a method of assisting a plane to rise from the water, I believe I have accomplished an urgent need for a device of this kind which is light in Weight, simple in operation and easily controlled.

In accordance with the patent statutes I have described the principles of operation of pontoon, and while I have endeavored to disclose the best embodiment thereof, I desire to have it understood that obvious changes may be made within the scope of the following claims Without departing from the spirit of the invention.

I. claim:

V 1. A pontoon for airplanes including, a pontoon for an airplane adapted to ride in the water to support the airplane on the water, tubular air v' aassageways extending over the under surface of said pontoon body and oppositely disposed openings in said tubular portions adapted to blow air under the pontoon to force the same out of the water when the airplane starts.

from the source of supply, it will pass out of said openings to force the pontoon out of the water at the time of the starting of the airplane.

3. A pontoon for an airplane including, tubular air pipes extendingon the outer surface along the bottom of said pontoon, a series of outlet openings in said air pipes and means for directing compressed air through said pipes through said openings to spread along the surface of the pontoon on either side of each of said pipes to overcome the water resistance on said pontoon at the time of the'starting of an airplane;

at. A pontoon for supporting an airplane on Water including, a body portion,passageways formed on the outer surface alongthe bottom of said pontoon adapted to direct compressed air to spread under the body of said pontoon on both sides of said passageways to assist in raising the same at the time of starting an airplane.-

I 5. A pontoon for supporting an airplane on the water including, a body portion adapted to float on the Water, air tubes extending along the outer surface of said pontoon in a manner to direct streams of compressed air through said air tubes to project on either side of said air tubes to overcome the water resistance against said pontoon in the starting of an airplane.

WVALTER lVALLR-AFF.

2. A pontoon for an airplane including, a-

body portion adapted to float on the Water to supportan. airplane, a supply tank for compressed air. and tubular members extending over and along the bottom of said pontoon on "the outer surface of the same hav of outlet openings oppositelydising a series posed on either side of said tubular members whereby when compressed air is released 

